Washing machine

ABSTRACT

A washing machine may include a cabinet; a washing tub which is disposed in the cabinet and in which a washing operation is performed; a liquid detergent supplier which contains and supplies a liquid detergent; a drawer-type container to which the liquid detergent supplier is coupled so as to be easily attachable and detachable and in which the liquid detergent supplier is contained; and a liquid detergent storage unit which is coupled to the drawer-type container, uniformly supplies the liquid detergent supplied by the liquid detergent supplier into the washing tub and detects whether the liquid detergent supplied by the liquid detergent supplier is stored therein.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from Korean Patent Application No. 10-2008-0048189 filed on May 23, 2008 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.

BACKGROUND

1. Field of the Disclosure

The present disclosure relates to a washing machine, and more particularly, to a washing machine which may store a liquid detergent, may detect the existence of a liquid detergent and may notify a user of the results of the detection.

2. Description of the Related Art

Liquid detergents are being commonly used in washing machines. Liquid detergents may improve washing performance and may maximize user convenience.

Conventional washing machines, however, are generally unable to determine whether there is a liquid detergent stored therein. Therefore, users may sometimes drive a washing machine without noticing that there is no liquid detergent in the washing machine. The washing machine thus will fail to properly perform the washing cycle. In addition, users may not be able to properly determine when to replace an existing liquid detergent supplier with a new liquid detergent supplier.

SUMMARY

Accordingly, a washing machine which detects the existence of a liquid detergent and thus allows a user to determine when to replace an existing liquid detergent supplier with a new liquid detergent supplier is highly desirable.

According to an aspect of the present disclosure, there is provided a washing machine including a cabinet; a washing tub which is disposed in the cabinet and in which a washing operation is performed; a liquid detergent supplier which contains and dispenses a liquid detergent; a storage drawer adapted to receive the liquid detergent supplier in a coupling relationship, such that the liquid detergent supplier can be easily attached and detached; and a liquid detergent reservoir, which is coupled to the storage drawer, is adapted to uniformly supply the liquid detergent, dispensed by the liquid detergent supplier, into the washing tub and is capable of detecting the presence or absence of the liquid detergent

According to another aspect of the present disclosure, it is possible to notify a user of the results of the detection performed by a liquid detergent detector regarding the existence of a liquid detergent. Therefore, it is possible for a user to easily recognize whether a liquid detergent is stored in the liquid detergent storage unit and thus to precisely determine when to replace the liquid detergent supplier with a new liquid detergent supplier. In addition, it is possible to prevent malfunction of the washing machine and improve user convenience by replacing the liquid detergent supplier with a new liquid detergent supplier at a proper time.

In addition, it is possible for a user to recognize whether a liquid detergent is stored in the liquid detergent storage unit and thus to determine when to replace an existing liquid detergent supplier with a new liquid detergent supplier. Therefore it is possible to improve the operating efficiency of a washing machine.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages will become more apparent in the detailed description of the preferred embodiments thereof with reference to the attached drawings in which:

FIG. 1 illustrates a perspective view of a laundry treatment machine according to an exemplary embodiment of the present disclosure;

FIG. 2 illustrates a cross-sectional view taken along line II-II of FIG. 1;

FIG. 3 illustrates a perspective view showing how a liquid detergent storage unit and a liquid detergent supplier shown in FIG. 2 are coupled to each other;

FIG. 4 illustrates a cross-sectional view taken along IV-IV of FIG. 3;

FIG. 5 illustrates a block diagram of a control mechanism of the laundry treatment machine shown in FIG. 1;

FIG. 6 illustrates an enlarged cross-sectional view of portion A of FIG. 4;

FIG. 7 illustrates a cross-sectional view of a variation of a liquid detergent sensing unit shown in FIG. 6; and

FIG. 8 illustrates a cross-sectional view of another variation of the liquid detergent sensing unit shown in FIG. 6.

DETAILED DESCRIPTION

Exemplary embodiments will hereinafter be described in detail with reference to the accompanying drawings. In the drawings, like reference numerals indicate like elements, and thus, detailed descriptions thereof will be omitted.

The term ‘washing machine’ as used herein indicates any type of device for washing objects such as dishes or clothes using a liquid detergent. The exemplary embodiments will hereinafter be described, taking a laundry treatment machine as an example. However, the present disclosure is not restricted to a laundry treatment machine.

FIG. 1 illustrates a perspective view of a laundry treatment machine 100 according to an exemplary embodiment of the present disclosure, and FIG. 2 illustrates a cross-sectional view taken along line II-II of FIG. 1. Referring to FIGS. 1 and 2, the laundry treatment machine 100 may include a cabinet having a top panel 114, a door 113, control panel 115, a washing tub 116 which is disposed in the cabinet 110 and in which laundry is washed, a wash water supply device which supplies wash water provided by an external water source into the washing tub, a drainage device which discharges wash water from the washing tub when a washing operation is complete, and a liquid detergent supply unit 150 which is disposed below the cabinet 110 and supplies a liquid detergent. The liquid detergent supply unit 150 may not necessarily be disposed below the cabinet 100 but may be disposed at various other locations in the laundry treatment machine 100. In this embodiment, the liquid detergent supply unit 150 may be disposed below the cabinet 110.

The washing tub may include a drum 122 in which laundry is washed and a driving device (not shown) which drives the drum 122.

FIG. 3 illustrates a perspective view showing how a liquid detergent storage unit 160 and a liquid detergent supplier 170 shown in FIG. 2 are coupled to each other, and FIG. 4 illustrates a cross-sectional view taken along IV-IV of FIG. 3. Referring to FIGS. 2, 3 and 4, the liquid detergent supply unit 150 may include the liquid detergent supplier 170 which supplies a liquid detergent, a drawer-type container 151 which is coupled to the liquid detergent supplier 170 so as to be able to be easily attached to or detached from the liquid detergent supplier 170 and in which the liquid detergent supplier 170 is contained, the liquid detergent storage unit 160 which is coupled to the drawer-type container 151 and uniformly supplies a liquid detergent supplied by the liquid detergent supplier 170 into the washing tub, the liquid detergent storage unit 160 which detects whether a liquid detergent is stored therein, and a liquid detergent guidance path 169 which guides the liquid detergent contained in the liquid detergent storage unit 160 into the washing tub.

The liquid detergent storage unit 160 may include a supply path 163 which guides a liquid detergent supplied by the liquid detergent supplier 170 into the liquid detergent storage unit 160, a liquid detergent reservoir 162 which stores the liquid detergent supplied by the liquid detergent supplier 170, a connector 164 which guides the liquid detergent stored in the liquid detergent reservoir 162 into the liquid detergent guidance path 169, and a liquid detergent detector 161 which determines whether a liquid detergent is stored in the liquid detergent reservoir 162. While the exemplary embodiment discloses a liquid detergent reservoir 162, it is also envisioned that the reservoir 162 may be eliminated such that a tube or the like is fluidly connected to the connector 164, and the liquid detergent detector 161 is disposed along a liquid detergent supply path to detect the presence of the detergent.

The supply of a liquid detergent into the liquid detergent storage unit 160 will now be described in detail. When a user inserts the liquid detergent supplier 170 into the drawer type container 151, a liquid detergent contained in the liquid detergent supplier 170 may flow into the liquid detergent reservoir 162 through the supply path 163. The liquid detergent reservoir 162 has an storage space therein and may thus be able to store a certain amount of liquid detergent therein. The liquid detergent stored in the liquid detergent reservoir 162 may be supplied to the washing tub when the laundry treatment machine 100 begins to be driven. More specifically, the liquid detergent stored in the liquid detergent reservoir 162 may be discharged from the liquid detergent storage unit 162 through the connector 164, and may then be supplied into a mixer 168. The mixer 168 may mix the liquid detergent supplied into with wash water provided by an external water source. Thereafter, the mixture of the liquid detergent and the wash water may be supplied into the drum 122 through a wash water bellows tub 147 and may thus be used to remove dust and dirt from laundry during a washing operation.

FIG. 5 illustrates a block diagram of a control mechanism of the laundry treatment machine 100. Referring to FIG. 5, when the laundry treatment machine 100 is driven and thus begins to perform a washing operation on laundry, a liquid detergent stored in the liquid detergent reservoir 162 may be supplied into the drum 122. During the supply of a liquid detergent into the drum 122, the liquid detergent detector 161 may detect the existence of a liquid detergent in the liquid detergent reservoir 162. If it is determined that a liquid detergent is stored in the liquid detergent reservoir 162, the liquid detergent detector 161 may transmit a signal indicating the existence of a liquid detergent in the liquid detergent reservoir 162 to a controller 180. The controller 180 may recognize the existence of a liquid detergent in the liquid detergent reservoir 162 based on the signal transmitted by the liquid detergent detector 161, and may decide not to output any signal to an output unit 190.

On the other hand, if it is determined that no liquid detergent is stored in the liquid detergent reservoir 162, the liquid detergent detector 161 may transmit a signal indicating that there is no liquid detergent stored in the liquid detergent reservoir 162 to the controller 180. The controller 180 may recognize that there is no liquid detergent stored in the liquid detergent reservoir 162 based on the signal transmitted by the liquid detergent detector 161 and may output a signal to the output unit 190. The output unit 190 may output an alarm signal based on the signal output by the controller 180 and may thus notify the user that there is no liquid detergent stored in the liquid detergent reservoir 162. The alarm signal may be an audio signal, for example, a buzzer or music signal. The alarm signal may also be a visual signal. Accordingly, the user may precisely recognize when to replace the liquid detergent supplier 170 with a new liquid detergent supplier 170 without having to periodically check the liquid detergent supplier 170. Therefore, it is possible to improve user convenience. In addition, it is possible to prevent the deterioration of the laundry treatment machine 100 performance due to a miscalculation of when to replace the liquid detergent supplier 170.

FIG. 6 illustrates an enlarged view of portion A of FIG. 4. Referring to FIG. 6, the liquid detergent detector 161 may be disposed above the liquid detergent reservoir 162. However, the location of the liquid detergent detector 161 is not restricted to that set forth herein. That is, the liquid detergent detector 161 may be disposed at any location from which the liquid detergent detector 161 can detect whether a liquid detergent is present in the liquid detergent reservoir 162. For example, the liquid detergent detector 161 may be disposed at a side of the liquid detergent reservoir 162. The liquid detergent detector 161 may include a first electrode 161 a and a second electrode 161 b facing the first electrode 161 a. An optical sensor may also be similarly implemented.

The operation of the liquid detergent detector 161 will hereinafter be described in detail with reference to FIGS. 4 and 6. A liquid detergent may be supplied into and stored in the liquid detergent reservoir 162 through the supply path 163. The liquid detergent reservoir 162 may have a single storage space therein. The liquid detergent reservoir 162 may also be divided into a first storage space 162 a and a second storage space 162 b. The second storage space 162 b may have a different height than the first storage space 162 a. When a liquid detergent is supplied into the liquid detergent reservoir 162 through the supply path 163, the first storage space 162 a may be filled first with the liquid detergent. Then, if the amount of liquid detergent supplied into the liquid detergent reservoir 162 exceeds the storage capacity of the first storage space 162 a and thus completely filling it, the second storage space 162 b may begin to be filled with a liquid detergent. The liquid detergent detector 161 may be disposed above the second storage space 162 b and may detect the existence of a liquid detergent in the liquid detergent reservoir 162. If the second storage space 162 b is filled with a liquid detergent, the first and second electrodes 161 a and 161 b may contact the liquid detergent. Once the first and second electrodes 161 a and 161 b contact a liquid detergent, a current may flow from the first electrode 161 a to the second electrode 161 b through the liquid detergent. The current may be converted into a signal by the liquid detergent detector 161, and the liquid detergent detector 161 may transmit the signal to the controller 180.

The controller 180 may process the signal transmitted by the liquid detergent detector 161 using the same method as or a similar method to that described above with reference to FIG. 5. Therefore, it is possible to determine whether a liquid detergent is stored in the liquid detergent reservoir 162. In addition, since the laundry treatment machine 100 outputs information indicating whether a liquid detergent is stored in the liquid detergent reservoir 162, it is possible to improve the operational convenience to the user.

The laundry treatment machine 100 may also include at least one protection unit disposed in the liquid detergent reservoir 162 and to protect the liquid detergent detector 161 against the fluctuation of a liquid detergent in the liquid detergent reservoir 162. The protection unit may be disposed near the liquid detergent detector 161 and may prevent the fluctuation of a liquid detergent stored in the liquid detergent reservoir 162 regardless of the movement of the liquid detergent reservoir 162. The protection unit may include a plurality of first and second protection elements 165 and 166. The first protection element 165 may prevent a liquid detergent supplied into the liquid detergent reservoir 162 through the supply path from contacting the liquid detergent detector 161. The second protection element 166 may prevent a liquid detergent stored in the liquid detergent reservoir 162 from colliding with the inner sidewalls of the liquid detergent reservoir 162 and contacting the liquid detergent detector 161.

That is, when the user opens the drawer-type container 161 in order to replace the liquid detergent supplier 170 with a new liquid detergent supplier 170, a liquid detergent stored in the liquid detergent reservoir 162 may collide with the bottom and the inner sidewalls of the liquid detergent storage unit 162 while constantly fluctuating in the liquid detergent reservoir 162. As a result, the liquid detergent in the liquid detergent reservoir 162 may contact the liquid detergent detector 161. If the liquid detergent contacts the liquid detergent detector 161, the first and second electrodes 161 a and 161 b may then be electrically connected. Then, the liquid detergent detector 161 may transmit a signal indicating that a liquid detergent is present in the liquid detergent storage unit 162 to the controller 180. In addition, when a liquid detergent is supplied into the liquid detergent storage unit 162 through the supply path 163, the liquid detergent may collide with the inner sidewalls of the liquid detergent storage unit 162 while constantly fluctuating in the liquid detergent storage unit 162. As a result, the liquid detergent may contact the first and second electrodes 161 a and 161 b. In this case, the liquid detergent detector 161 may malfunction spring a false reading. Thus, the controller 180 may mistakenly determine that a liquid detergent is stored in the liquid detergent storage unit 162 when it actually is not.

If the first and second protection elements 165 and 166 are installed in the liquid detergent reservoir 162, however, the liquid detergent may fluctuate, but will be prevented from spilling over despite collisions with the first protection element 165. Even if the liquid detergent in the liquid detergent reservoir 162 spills over the first protection element 165, the second protection element 166, which is disposed near the liquid detergent detector 161, may prevent the liquid detergent from contacting the liquid detergent detector 161. If the liquid detergent reservoir 162 is moved, the liquid detergent in the liquid detergent storage unit 162 may collide with the inner sidewalls of the liquid detergent storage unit 162 and constantly fluctuate. In this case, the second protection element 166 may also prevent the fluctuating liquid detergent from contacting the liquid detergent detector 161. Therefore, it is possible to prevent the liquid detergent detector 161 from malfunctioning when the user opens the drawer-type container 161 or similar situations where the level of the liquid detergent may suddenly fluctuate. Thus, it is possible for the user to properly determine the state of the liquid level in the liquid detergent storage unit 162 and to precisely determine when to replace an old liquid detergent supplier 170 with a new liquid detergent supplier 170.

FIG. 7 illustrates a cross-sectional view of a variation of the liquid detergent detector 161 shown in FIG. 6, i.e., a liquid detergent detector 161′. In FIGS. 6 and 7, like reference numerals indicate like elements. The exemplary embodiment of FIG. 7 will hereinafter be described in detail, mainly focusing on differences with the exemplary embodiment of FIG. 6.

Referring to FIG. 7, the liquid detergent detector 161′ may include a plurality of liquid detergent detectors 161 a′ through 161 d′. The second liquid detergent detector 161 b′ may be formed to a greater height than the first liquid detergent detector 161 a′. the third liquid detergent detector 161 c′ may be formed to a greater height than the second liquid detergent detector 161 b′, and the fourth liquid detergent detector 161 d′ may be formed to a greater height than the third liquid detergent detector 161 c′.

When a liquid detergent is supplied into a liquid detergent reservoir, the liquid detergent reservoir begins to be filled with the liquid detergent. As the supply of a liquid detergent into the liquid detergent reservoir continues, the liquid level may gradually increase from the height of the first liquid detergent detector 161 a′ to the height of the second liquid detergent detector 161 b′, from the height of the second liquid detergent detector 161 b′ to the height of the third liquid detergent detector 161 c′ and from the height of the third liquid detergent detector 161 c′ to the height of the fourth liquid detergent detector 161 d.′ The liquid detergent detector 161 may transmit a signal indicating an amount of liquid detergent corresponding to the height of the first, second, third or fourth liquid detergent detector 161 a′, 161 b′, 161 c′, or 161 d′ has been supplied into the liquid detergent reservoir to the controller 180 whenever the liquid level in the liquid detergent reservoir exceeds the height of the first, second, third or fourth liquid detergent detector 161 a′, 161 b′, 161 c′, or 161 d′.

On the other hand, as the amount of liquid detergent supplied by the liquid detergent supplier 170 decreases and the consumption of the liquid detergent stored in the liquid detergent reservoir continues, the liquid level may gradually decrease from the height of the fourth liquid detergent detector 161 d′ to the height of the third liquid detergent detector 161 c,′ from the height of the third liquid detergent detector 161 c′ to the height of the second liquid detergent detector 161 b′, and from the height of the second liquid detergent detector 161 b′ to the height of the first liquid detergent detector 161 a′.

The liquid detergent detector 161 may transmit a signal indicating an amount of liquid detergent corresponding to the height of the first, second, third or fourth liquid detergent detector 161 a′, 161 b′, 161 c′, or 161 d′ still remains into the liquid detergent reservoir to the controller 180 whenever the liquid level in the liquid detergent reservoir reaches the height of the fourth, third, second or first liquid detergent detector 161 d′, 161 c′, 161 b′, or 161 a′.

The controller 180 may set a predetermined reference level in advance. Then, if the amount of liquid detergent detected by the liquid detergent detector 161′ is less than the reference level, the controller 180 may notify a user of the amount of liquid detergent stored in the liquid detergent storage unit by outputting a signal. Therefore, it is possible for the user to precisely determine when to replace an existing liquid detergent supplier with a new liquid detergent supplier based on the amount of liquid detergent stored in the liquid detergent storage.

FIG. 8 illustrates a cross-sectional view of a variation of the liquid detergent detector 161 shown in FIG. 6, i.e. a liquid detergent detector 161″. In FIGS. 6 and 8, like reference numerals indicate like elements. The exemplary embodiment of FIG. 8 will hereinafter be described in detail, mainly focusing on differences with the exemplary embodiment of FIG. 6.

Referring to FIG. 8, the liquid detergent detector 161″ may include a floater 161 a″ floating on the liquid detergent in a liquid detergent reservoir and a liquid level measurer 161 b″ determining the liquid level in the liquid detergent reservoir by measuring the height of the floater 161 a″ above the bottom of the liquid detergent reservoir. That is, when a liquid detergent is supplied into the liquid detergent reservoir, the liquid detergent reservoir begins to be filled with the liquid detergent. Then, the liquid detergent begins to flow into the liquid detergent detector 161″ including the floater 161 a″. A barrier wall 169 may be disposed in the liquid detergent storage unit and may divide the liquid detergent detector 161″ from the rest of the liquid detergent storage. The barrier wall 169 may include, for example, a hole or a plurality of holes through which a liquid detergent can pass. Thus, liquid detergent may flow into the liquid detergent detector 161″ through the hole of the barrier wall 169.

If a liquid detergent flows into the liquid detergent detector 161″, the level in the liquid detergent detector 161″ may increase, and the floater 161 a″ may float on the liquid detergent.

The liquid level measurer 162 b″ may then determine the location of the floater 161 a″. For this, the floater 161 a″ may include a magnetic material (not shown) generating magnetic force, and the liquid level measurer 162 b″ may include a magnetic force detector (not shown) measuring the magnetic force generated by the magnetic material. The liquid lever measurer 161 b″ may measure the liquid level in the liquid detergent detector 161″ by determining the point at which the magnetic force generated by the floater 161 a″ is detected. Thereafter, the liquid level measurer 161 b″ may transmit the result of the measurement to a controller 180. Then, the controller 180 may determine the amount of liquid detergent stored in the liquid detergent storage unit based on the result of the measurement performed by the liquid level measurer 161 b″ and may output a signal to a user with the use of an output unit (not shown). Therefore, it is possible for a user to precisely determine when to replace an existing liquid detergent supplier with a new liquid detergent supplier. Alternatively, the liquid detergent detector 161 b″ may include a device mechanically moving in accordance with the liquid level in the liquid detergent detector 161 b″. Any type of device may be used as the liquid detergent detector 161″ as long as it can measure the liquid level in the liquid detergent reservoir 162.

In this manner, it is possible for the user to precisely determine when to replace an existing liquid detergent supplier with a new liquid detergent supplier. In addition, it is possible to improve the performance of a laundry treatment machine by replacing an existing liquid detergent supplier with a new liquid detergent supplier at a proper time.

While the exemplary embodiments have been particularly shown and described using references to, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure. 

1. A washing machine comprising: a cabinet; a washing tub which is disposed in the cabinet; a liquid detergent storage unit comprising: a storage drawer adapted to receive a liquid detergent supplier, which contains and dispenses a liquid detergent, in a coupling relationship, such that the liquid detergent supplier can be attached and detached; and a liquid detergent reservoir, which is coupled to the storage drawer, is adapted to supply the liquid detergent, dispensed by the liquid detergent supplier, into the washing tub and is capable of detecting the presence or absence of the liquid detergent.
 2. The washing machine of claim 1, further comprising a liquid detergent guidance path which guides the liquid detergent stored in the liquid detergent storage unit into the washing tub, the liquid detergent storage unit further comprising: a supply path guiding the liquid detergent supplied by the liquid detergent supplier; a connector guiding the liquid detergent stored in liquid detergent storage unit into the liquid detergent guidance path; and a liquid detergent detector to determine whether a liquid detergent is present in the liquid detergent storage unit.
 3. The washing machine of claim 2, wherein the liquid detergent detector is disposed above the liquid detergent reservoir.
 4. The washing machine of claim 2, wherein the liquid detergent detector includes a first electrode and a second electrode facing the first electrode, and the first and second electrodes are in electrical communication when contacting the liquid detergent.
 5. The washing machine of claim 2, the liquid detergent detector comprising: a floater that can float on the liquid detergent stored in the liquid detergent reservoir in accordance with a liquid level in the liquid detergent reservoir; and a liquid level measurer that can determine the liquid level in the liquid detergent reservoir by measuring the distance of the floater from a bottom of the liquid detergent reservoir.
 6. The washing machine of claim 2, further comprising at least one protection unit which is disposed in the liquid detergent reservoir and protects the liquid detergent detector from improperly reading liquid detergent movement near inner sidewalls of the liquid detergent reservoir.
 7. The washing machine of claim 6, wherein the protection unit includes a first protection element preventing a liquid detergent supplied into the liquid detergent through the supply path from contacting the liquid detergent detector and a second protection element preventing the liquid detergent stored in the liquid detergent reservoir from contacting the liquid detergent detector due to external collisions with the inner sidewalls of the liquid detergent reservoir.
 8. The washing machine of claim 2, further comprising at least one protection unit which is disposed near the liquid detergent detector and prevents the liquid detergent stored in the liquid detergent reservoir from fluctuating in accordance with the movement of the liquid detergent reservoir.
 9. The washing machine of claim 2, further comprising an output unit which outputs a signal to a controller and notifies a user if a liquid detergent is present in the liquid detergent reservoir if the liquid detergent storage unit detects the presence of a liquid detergent.
 10. A method for controlling a liquid detergent dispenser in a washing machine comprising: dispensing a liquid detergent from a liquid detergent supplier into a liquid detergent reservoir; detecting the presence of the liquid detergent in the liquid detergent reservoir after a predetermined amount of time has passed; generating a signal indicating a liquid detergent level; and indicating to a user the liquid detergent level.
 11. The method of claim 10 further comprising: stopping operation of a pump adapted to dispense liquid detergent when an absence of liquid detergent is detected.
 12. A washing machine comprising: a cabinet; a washing tub which is disposed in the cabinet; a storage drawer adapted to receive a liquid detergent supplier, which contains and dispenses a liquid detergent, in a coupling relationship, such that the liquid detergent supplier can be attached and detached; and a connecting part to receive the liquid detergent supplier such that the connecting part can fluidly receive and guide the liquid detergent along a supply path so that the liquid detergent can be automatically introduced into a washing cycle.
 13. The washing machine of claim 12, further comprising: a liquid detergent detector disposed along the supply path to determine whether a liquid detergent is present. 